The History of the Vacuum Cleaner Goes Back to the 1860s. The device has grown from being a home appliance to one that is used extensively in commercial and industrial settings. There are leaf vacuums, storm-drain vacuums and, now, at Connecticut Light & Power (CL&P; Berlin, Connecticut, U.S.), a wood-chip vacuum — the first of its kind in use by a utility in New England and possibly in the United States.

NECESSITY AND INVENTION

CL&P has one of the most heavily wooded service territories in the utility industry. Tree trimming and the resulting wood chips have to be dealt with on a daily basis. The chips have always been a waste-product issue. The simplest way to get rid of them in rural areas has been to blow them off the road. But that doesn't work in any of the communities CL&P serves.

Instead, the practice has been for the tree-trimming crews to blow the chips into the back of a truck and then find a place to dump them. Sometimes a homeowner down the street from a trimming job wants them, but more often, the crew ends up hauling them away from the work site. This means the crew has to stop what it is doing, pack up and drive off to a dump site. This results not only in lost time on the job, but the expense of US$40/ton to $50/ton just to get rid of the chips.

As the saying goes, “Necessity is the mother of invention.”

CL&P — part of the Northeast Utilities System — teamed up with Lewis Tree Service Inc. (West Henrietta, New York) to design and build a wood-chip vacuum.

The invention came about from sketching ideas on napkins and pieces of paper. The sketches provoked a torrent of questions. How would it be possible to build it? What would the dimensions be? Who would build it? None of the equipment manufacturers with whom CL&P and Lewis were working had ever built something like this. While machinery such as a storm-drain vacuum was commonplace, the idea for the Chip Vac was an entirely different story.

Municipal Equipment Sales (Woodstock, Georgia, U.S.) was approached to build a prototype. The first Chip Vac, however, was too small and lacked the necessary power and capacity. Also, there was an issue with dust. At the initial test, there was dust flying everywhere and everything within a 200-ft (61-m) radius was covered. Clearly, some redesigning and tweaking were necessary.

So, the process moved from sketches on napkins to engineered drawings. The Chip Vac went from a two-axle truck to a three-axle truck with more capacity and more power. Today, the truck is 29 ft (9 m) long, 11 ft (3 m) high and 8 ft (2 m) wide. The 52,000-lb gross vehicle weight chassis has a storage capacity of 38 cu yds (29 cu m).

Currently, the Chip Vac is being used in Fairfield County, Connecticut, but CL&P would like to use the vehicles across its entire service territory. CL&P serves 149 of Connecticut's 169 towns and is talking with Lewis about building more of them. The staff at Lewis is already looking beyond Connecticut with plans to build several models in 2009 for use in New York City, the Baltimore, Maryland-Washington, D.C. area and possibly Florida. The first Chip Vac took eight months to build. They are custom built at a current cost of about $250,000 each.

BIOMASS MANAGEMENT SYSTEM

While the name Chip Vac 3000 Biomass Management System doesn't exactly roll off the tongue, the machine is already proving its worth. The Chip Vac can collect and dispose of chips from 14 aerial-lift tree crews every day, or the equivalent of more than 30 tons (27 metric tons) of wood chips. Tree crews no longer have to leave the job site to dump their chips, meaning less travel time, and less wear and tear on the trucks. That translates into an increased tree-crew productivity of about one hour per crew per day, with no municipal dumping fees.

The improved efficiency has been obvious from the start. There are 14 Lewis crews currently using the Chip Vac in Connecticut. Estimate $100 per hour per crew, and that crew is now avoiding an hour per day of dumping chips, that's $1400 a day. Contrast that with the cost of the Chip Vac and the operator at $75 per hour for nine hours, which comes to $675. In other words, CL&P is saving its customers $725 a day right off the top. And tree trimming and chipping is a year-round endeavor. Considering the savings, it is shocking how long it took to convince some people of the value of the machine.

SOME GIANT STEPS

This model is the first step in the evolution of the Chip Vac for the tree-care industry. The next version will have several improvements. Currently, the driver must physically attach the hose to the vacuum before beginning a job. In future versions, the driver will be able to operate everything from the cab. Cameras will be mounted all around the truck, so the operator can see all sides.

Lewis Tree Service's Chip Vac mechanic and operator in Connecticut have developed a commercial mesh that helps keep all the dust inside the box. They have also helped re-design the hose and the motor to give the operator more flexibility. The operator will have the option of transferring chips from truck to truck, instead of only being able to pull up to a pile.

A MULTI-SIDED OPPORTUNITY

Simply dumping wood chips may soon become a thing of the past. The next step in the wood-chip management process is marketing the chips. The Chip Vac makes it practical to collect and sell what had been traditionally a waste product.

This is a huge opportunity for tree-trimming companies in urban environments across the United States. They will have the ability to take a waste product and turn it into a commodity. Wood chips can be moved from the expense side to the revenue side of the balance sheet.

At a time when there is widespread national attention on developing alternatives to fossil fuels, wood chips can be an easily attainable energy source. Northeast Utilities already has a wood-chip-burning power plant in Portsmouth, New Hampshire, U.S. There are four biomass plants on the drawing board in Connecticut. Three would burn the chips, while the fourth would turn the chips into ethanol.

Other East Coast utilities are pursuing turning wood waste into a commodity. These utilities see wood chips as a potential revenue source. Urban utilities are in close proximity to rail lines and are looking into shipping the chips to New Hampshire and other plants that burn wood and wood waste.

Wood chips of 1 ton (0.9 metric tons) can produce 60 to 70 gallons (227 to 265 liters) of ethanol. Since flex-fuel vehicles burn 85% ethanol, there is tremendous potential for the tree-care industry at large. Wood chips produce a green fuel that can easily be marketed as homegrown.

The time may be coming when an enterprising individual might buy a Chip Vac and contract with Lewis or another line-clearance contractor or people in the private tree-clearing business. The business model would include using the Chip Vac as a collection service and then selling the collection to a power plant. The people who will really show great interest are the folks who need hundreds of thousands of tons to run their biomass energy plants. And, there is also a Connecticut-based wood-brick manufacturer who apparently can't keep up with customer demand for his product and whose plant is running 24 hours a day.

WHAT ABOUT THAT NAME?

Where did the Chip Vac 3000 Biomass Management System come from? The 3000 is just a forward-looking number. It came about during a conversation with Bill Van Cura, regional vice president for Lewis, back in the sketches-on-napkins days about what to call the machine. It seemed that just calling it a chip vacuum wasn't enough. The part about being a biomass management system speaks to a wider audience, as well as to the wider potential of the concept. Biomass is more than wood chips and is seen as a different product. The current name has a more-environmental appeal, and the concept of biomass to energy has a lot of attention.

The Chip Vac is quickly proving its value through improved crew productivity and reduced costs. Biomass is on the rise as a clean, homegrown, renewable energy source. Wood chips are in demand. There are countless economic and environmental benefits to the Chip Vac.

In the future, not only will chip vacuums be collecting chips from utility line-clearance jobs and private tree-care crews be using the Chip Vacs for their jobs, but they'll all be bringing the chips to market as biofuel — from trash to treasure.

David Goodson (goodsda@nu.com) is a manager in Northeast Utilities' vegetation management department and has been with the company since 1980. He is a member of the International Society of Arboriculture, Utility Arborist Association and the Connecticut Tree Protective Association.